Process for producing a phase difference control component and liquid crystal display device

ABSTRACT

There are provided a phase difference control component, which can realize a liquid crystal display device having a wide angle of visibility, has excellent phase difference symmetry and can realize optical compensation, and a process for producing the same. The phase difference control component comprises a base material; and a phase difference control layer formed of a fixed liquid crystal material provided on the base material through an aligning film and is characterized in that the angle of liquid crystal molecules, present at the interface of the aligning film and the phase difference control layer, to the base material being substantially 0 (zero) degree.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/654,428, filed Oct. 16, 2019, which is a continuation of U.S.application Ser. No. 16/229,330, filed Dec. 21, 2018, now U.S. Pat. No.10,481,436, which issued on Nov. 19, 2019, which is a continuation ofU.S. application Ser. No. 15/092,933, filed Apr. 7, 2016, now U.S. Pat.No. 10,203,555, which issued on Feb. 12, 2019, which is a continuationof U.S. application Ser. No. 12/365,402, filed Feb. 4, 2009, nowabandoned, which in turn is a division of U.S. application Ser. No.11/175,959, filed Jul. 6, 2005, now abandoned, the entireties of whichare incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a phase difference control componentcomprising a liquid crystal material, which has excellent symmetry withrespect to the angle of visibility and is optically compensable, and aprocess for producing the same, and a liquid crystal display devicecomprising said phase difference control component.

Background Art

Color liquid crystal displays (hereinafter often referred to as “LCDs”)have features such as thin shape, light weight, low power consumption,and flickerless, and the market of color liquid crystal displays for PCsincluding notebook computers has been rapidly grown. In recent years,regarding displays for PCs, there is an increasing demand for desktopmonitors which are larger in size than notebook computers. Further, LCDshave become utilized in PCs, as well as in TVs for which CRTs havehitherto been mainly utilized.

A small angle of visibility is a problem inherent in LCDs. This problemis caused by light leakage from pixels, which should originally displayblack, when LCDs are viewed in an oblique direction. Due to this lightleakage, the inversion of contrast takes place, and proper displaybecomes impossible. As a result, the angle of visibility is lowered.

In order to solve the above problem, LCDs with a high angle ofvisibility using a phase difference film have been proposed. The phasedifference film is also used in combination with a linear polarizationplate for creating various polarized states. For example, circularlypolarized light can generally be constituted by a combination of alinearly polarizing plate with a λ/4 (quarter-wave) phase differenceplate.

In these phase difference films, transparent polymeric films such aspolycarbonate films subjected to stretching treatment such as monoaxialstretching have hitherto been used. In addition to these films, filmsformed by aligning and fixing a liquid crystal material havingrefractive index anisotropy while imparting given regularity can also beused. The phase difference film using a liquid crystal material canconstitute, through alignment control of liquid crystal molecules,positive and negative A plates, positive and negative C plates, and aphase difference layer with hybrid alignment in which the aligned stateis continuously varied (see, for example, Japanese Patent Laid-Open No.11-153712 A1).

An aligning film subjected to alignment treatment is necessary forhorizontally aligning liquid crystal molecules against a base materialin a monoaxial direction. In general, polyimide films subjected torubbing treatment are generally used as the aligning film. When liquidcrystal molecules are aligned in a rubbing direction on the aligningfilm subjected to rubbing treatment, a pretilt angle (an angle of liquidcrystal molecules to the base material) is created so that the end ofthe liquid crystal molecules are lifted in the rubbing directionrelative to the base material. This pretilt angle plays an importantrole in regulating the liquid crystal molecules so that, upon voltageapplication, the liquid crystal molecules are lifted unidirectionally.Therefore, the presence of a pretilt angle in the liquid crystalmolecules is indispensable, and, at the same time, the pretilt angleshould be controlled.

When a fixed liquid crystal material is used as the phase differencecontrol component, however, the presence of a pretilt angle in liquidcrystal molecules causes a change in the level of phase difference tobecome asymmetrical with respect to the vertical direction upon a changein angle of visibility in a direction other than the phase advance axis.In particular, when the angle of visibility is varied in an optical axisdirection of liquid crystal molecules, the asymmetry of a change inlevel of the phase difference is most significant.

Specifically, in the formation of an aligning film by the conventionalrubbing method, as shown in FIG. 2, an aligning film 22 is coated on abase material 21 (FIG. 2 (a)). The aligning film is rubbed, for example,by a rubbing roller 23 or the like (FIG. 2 (b)). Next, a liquid crystalmaterial is coated on the aligning film subjected to rubbing treatment.Molecular liquid crystals 24 make a pretilt angle θ with the directionof rotation of the rubbing roller 23 for alignment (FIG. 2 (c)).

For this reason, when the level of phase difference is measured byvarying the observation angle in a direction other than the phaseadvance axis, the level of the phase difference is asymmetrical withrespect to 0 (zero) degree (vertical direction). In particular, when thelevel of phase difference is measured by varying the observation anglein the direction of the slow phase axis, the asymmetry of the level ofthe phase difference is most significant. For this reason, a liquidcrystal display device to which a phase difference control componentformed of a liquid crystal material with a pretilt angle θ has beenapplied, suffers from a problem that, except for a change in observationangle in the phase advance axis, display images are different.

Since the pretilt angle also propagates in the thickness-wise directionof the film, when the phase difference layer comprises a plurality ofliquid crystal layers stacked on top of each other, the alignment at theinterface of the liquid crystal layers is adversely affected.

For oblique compensation of angle of visibility, the necessary phasedifference level should be calculated for design of the phase differencecontrol component. When the level of the symmetry of the angle ofvisibility is low, a desired phase difference level can be realized onlyin any one direction and a phase difference control component, which canrealize a satisfactorily large angle of visibility, cannot be provided.

In large-size liquid crystal televisions, due to properties of angle ofvisibility within a display face attributable to the large area, thesymmetry of the angle of visibility poses a severe problem.

SUMMARY OF THE INVENTION

The present inventors have now found that, when the pretilt angle ofliquid crystal molecules constituting a phase difference controlcomponent is substantially 0 (zero) degree, the asymmetry of the phasedifference does not occur. The present invention has been made based onsuch finding.

Accordingly, an object of the present invention is to provide a phasedifference control component, which has excellent phase differencesymmetry and is optically compensable, capable of realizing a liquidcrystal display device having a wide angle of visibility, and a processfor producing the same.

The phase difference control component according to the presentinvention comprises: a base material; and a phase difference controllayer formed of a fixed liquid crystal material provided on said basematerial through an aligning film, characterized in that the angle ofliquid crystal molecules, present at the interface of the aligning filmand the phase difference control layer, to the base material issubstantially 0 (zero) degree.

The process for producing a phase difference control component accordingto the present invention is characterized by comprising at least thesteps of:

forming an aligning film on a base material; and

providing a liquid crystal material on said aligning film and applyingalignment controlling force to the liquid crystal material to form aphase difference control layer,

the application of the alignment controlling force to the liquid crystalmaterial being carried out by a photoalignment method in whichcollimated deflected light is applied to the alignment film from thevertical direction.

In the present invention, the expression “a pretilt angle ofsubstantially 0 degree” means that, although, when liquid crystalmolecules are microscopically observed, the liquid crystal molecules arevery slightly tilted against the base material surface, since there isno regularity in the direction of lifting of the tilt, when the liquidcrystal molecules are macroscopically observed, lifting angles areoffset and, consequently, the pretilt angle is observed to be 0 degree.

In the phase difference control component according to the presentinvention, any pretilt angle does not exist in the liquid crystalmolecules constituting the phase difference member. Therefore, the levelof the phase difference symmetry is so high that the angle of visibilityof the liquid crystal display device can be effectively increased.Further, a liquid crystal display device, which is excellent in symmetryof the angle of visibility, can be realized.

Further, in the process according to the present invention, inconstructing a phase difference control component using a liquid crystalmaterial, a phase difference layer having a pretilt angle ofsubstantially 0 degree can be formed by using a photoalignment methodand applying ultraviolet light in the vertical direction. Therefore,when the level of phase difference is measured by varying theobservation angle in the slow phase axis direction, highly symmetricalphase difference control can be realized and, thus, a phase differencecontrol component which can realize higher-accuracy optical compensationcan be provided.

Further, according to the present invention, when the phase differencecontrol component is stacked directly on a color filter, ahigher-performance phase difference control component free fromshrinkage with the elapse of time and peel-off which are problems of theconventional film-type phase difference control component can beprovided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view illustrating a production process of aphase difference control component comprising a liquid crystal materialby a photoalignment method according to the present invention;

FIG. 2 is a cross-sectional view illustrating the step of aligning analigning film by the conventional rubbing method;

FIG. 3 is an explanatory view illustrating the case where the level ofthe phase difference is measured by varying the observation angle in theslow phase axis direction to positive values and negative valuesrelative to 0 degree;

FIG. 4 is a diagram showing the results of measurement of retardationvalues (Re; nm) representing the level of phase difference by varyingthe observation angle (an elevation angle) of a phase difference controlcomponent in the working example in the range of −45 degrees to +45degrees in the slow phase axis direction; and

FIG. 5 is a diagram showing the results of measurement of retardationvalues (Re in nm) representing the level of phase difference by varyingthe observation angle (an elevation angle) of a phase difference controlcomponent in the range of −45 degrees to +45 degrees in the slow phaseaxis direction by the conventional rubbing method for comparison withthe working examples of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described in detail withreference to the accompanying drawings.

The phase difference control component according to the presentinvention has a structure comprising a phase difference control layerprovided on a base material through an aligning film. Individual layersconstituting the phase difference control component according to thepresent invention will be described.

Base Material

As shown in FIG. 1 (a), a base material 11 on which an aligning film 12is provided is either an inorganic base material, for example, a glasssubstrate formed of glass or quartz or silicon, or an organic basematerial.

Organic base materials include plastic substrates or films formed ofpolymethyl methacrylate or other acrylic resins, polyamides,polyacetals, polybutylene terephthalates, polyethylene terephthalates,polyethylene naphthalates, triacetylcelluloses, syndiotacticpolystyrenes, polyphenylene sulfides, polyether ketones, polyether etherketones, fluororesins, polyethernitriles, polycarbonates, modifiedpolyphenylene ethers, polycyclohexenes, polynorbornenes resins,polysulfones, polyethersulfones, polysulfones, polyallylates,polyamide-imides, polyetherimides or thermoplastic polyimides. However,it should be noted that the organic base material is not limited tothose described above and conventional plastic films and the like mayalso be used.

Further, the above-described glass substrates, plastic substrates andsubstrates comprising a color filter provided on a film may also be usedas the base material.

The thickness of the base material 11 is not particularly limited andmay vary depending upon applications, and, for example, base materialhaving a thickness of about 1 nm to 5 μm may be used.

A substrate provided with a color filter may also be used as the basematerial. For example, a construction may also be adopted in which analigning film is provided on a color filter and a phase differencecontrol layer formed of a liquid crystal material is then stacked.

Aligning Film

The aligning film used in the present invention may be formed by thefollowing method. A solution of an aligning film material dissolved in asolvent is prepared. This solution is coated onto the base material 11by spin coating, flexographic printing or the like to form a coatingfilm. Thereafter, the solvent is removed from the coating film to forman unaligned aligning film. Next, the aligning film is subjected toalignment treatment. Alignment methods usable in the present inventionfor bringing the pretilt angle of liquid crystal molecules tosubstantially 0 degree include photoalignment, and rubbing treatment foraligning liquid crystal molecules in a direction perpendicular to therubbing direction.

FIG. 1 (b) shows the step of subjecting an aligning film to aphotoalignment alignment treatment. Specifically, collimated polarizedlight (ultraviolet light) 13 is applied to the aligning film 12 providedon the base material 11 for alignment of the aligning film 12 byphotoalignment. In the present invention, alignment methods using thephotoalignment are roughly divided into photoisomerization types andphotoreaction types according to the reaction mechanism. Photoreactiontypes are further subdivided into dimerization types, decompositiontypes, bonding types and the like.

One example of the photoisomerization type is azobenzene which causescis-trans isomerization. Azobenzene absorbs ultraviolet light of anelectric field vector parallel to the molecular axis and consequently isconverted from trans form to cis form. Liquid crystal molecules arealigned parallel to azobenzene in trans form and thus are aligned in adirection perpendicular to the polarization direction of ultravioletlight. Accordingly, an aligning film having a pretilt angle ofsubstantially 0 degree can be prepared.

Photoreaction types include dimerization of polyvinyl cinnamate,decomposition of polyimide resin, and bonding of polyimide having abenzophenone skeleton. All of these methods can form aligning filmshaving a pretilt angle of 0 degree.

A rubbing technique for aligning liquid crystal molecules in a directionvertical to the rubbing direction may be mentioned as another alignmentmethod for bringing the pretilt angle of liquid crystal molecules tosubstantially 0 degree.

For example, conventional aligning films disclosed in Japanese PatentLaid-Open Nos. 2002-062427 A1 and 2002-268068 A1 may be used as thealigning film in this method. Specifically, aligning films, in which thepretilt angle of liquid crystal molecules is substantially 0 degree, canbe prepared by using modified polyvinyl alcohols or polyimide orpolyamic acid having a carbazole skeleton on its side chain.

Phase Difference Control layer

In the present invention, the phase difference control layer 14 providedon the aligning film 12 is formed of a liquid crystal material. Afterthe alignment treatment, the liquid crystal material should be fixedwhile maintaining the alignment. FIG. 1 (c) shows a phase differencecontrol layer 14 in such a state that liquid crystal molecules 15 havebeen aligned to a pretilt angle of substantially 0 degree. In thedrawing, the liquid crystal molecules 15 are shown in a typicallyenlarged state.

Subsequently, the liquid crystal material is fixed while holding thealignment of the liquid crystal molecules 15. In this case, from theabove viewpoint, preferred liquid crystal materials include polymericliquid crystal materials, which have a glass transition temperature and,at a temperature below the glass transition temperature, can realizefixation of the liquid crystal structure, and photopolymerizable liquidcrystal materials which can be cured by three-dimensional crosslinkingupon exposed to ultraviolet light.

Monomer molecules which are three-dimensionally crosslinkable uponexposure to ultraviolet light include a mixture of a liquid crystalmonomer and a chiral compound, as disclosed, for example, in JapanesePatent Laid-Open No. 07-258638 A1 and Published Japanese Translation ofPCT Publication No. 10-508882 T. For example, compounds represented bythe following formulae (I) to (XI) or a mixture composed of two or moreof them are suitable for use as the photopolymerizable liquid crystalmaterial. In the liquid crystal monomer represented by formula (XI),preferably, X is 2 to 5 (integer).

Compounds having chemical structures represented by the followingformulae (XII) to (XIV) are suitable as chiral agents.

In the chiral agents represented by formulae (XII) to (XIII), Yrepresents any one substituent selected from substituents represented bythe following formulae (i) to (xxiv), and R₄ represents hydrogen or amethyl group. X is preferably 2 to 12 (integer).

In the chiral agent represented by formula (XIV), X is preferably 2 to 5(integer).

The phase difference control layer 14 may be formed by providing theabove photopolymerizable liquid crystal material or polymeric liquidcrystal material, optionally dissolving or diluting the material with asolvent, coating the material onto a base material by spin coating, diecoating, slit coating or other proper method, and removing the residualsolvent, for example, by heat drying. Thereafter, a liquid crystalstructure in which liquid crystal molecules have been aligned at apretilt angle of substantially 0 degree is developed in the liquidcrystal material.

When a photopolymerizable liquid crystal material is used, as shown inFIG. 1 (d), ultraviolet light 16 is then applied to polymerize thephotopolymerizable liquid crystal material, whereby a phase differencecontrol layer 14 formed of a liquid crystal material, which holds aliquid crystal structure with liquid crystal molecules aligned at apretilt angle of substantially 0 degree, can be formed.

In the present invention, preferably, the phase difference control layerhas positive birefringence properties, and the optical axis thereof isparallel to the plane of the phase difference control layer.

In the present invention, a two-layer construction may also be adoptedin which a second phase difference control layer, which has negativebirefringence properties and has an optical axis perpendicular to theplane of the phase difference control component is stacked on the phasedifference control layer which has positive birefringence properties andhas an optical axis parallel to the plane of the phase differencecontrol component.

Further, in the present invention, another two-layer construction mayalso be adopted in which a second phase difference control layer, whichhas positive birefringence properties and has an optical axisperpendicular to the plane of the phase difference control layer isstacked on a first phase difference control layer which has positivebirefringence properties and has an optical axis parallel to the planeof the phase difference control layer.

The phase difference control component according to the presentinvention, together with a color filter, may constitute a laminatestructure. For example, when a phase difference control layer having anoptical axis parallel to the plane of the phase difference control layeris stacked on a color filter, a method may be adopted in which aphotopolymerizable liquid crystal composition comprising aphotopolymerization initiator incorporated in a polymerizable liquidcrystal monomer is coated onto one side of a color filter to form acoating which is then exposed to ultraviolet light or the like to form acontinuous one layer stacked on the color filter. On the other hand,when a phase difference control layer having an optical axisperpendicular to the plane of the phase difference control layer isstacked, this layer can be formed in the same manner as described above,except that a photopolymerizable liquid crystal composition containing apolymerizable chiral agent is used.

The laminate structure in which the phase difference control componentis stacked directly on the color filter can realize a high-performancephase difference control component free from shrinkage with the elapseof time and peeling which are problems of the conventional film-typephase difference control component.

In forming the phase difference control component on the color filter,in some cases, the underlying color filters are different from eachother in thickness depending upon color patterns of red, blue, andgreen, that is, the surface of the color filters is uneven. In thiscase, preferably, a method is adopted in which the color filter isflattened by providing a transparent flattening layer on the colorfilter and the phase difference control component is then formed on theflattening layer.

Further, in an embodiment of the present invention, a color filter isstacked on a phase difference control component.

Examples

The following Examples further illustrate the present invention.However, it should be noted that the present invention is not limited tothese Examples.

1. Preparation of Base Material with Aligning Film

A glass substrate (1737 glass, manufactured by Corning Inc.) which hadbeen cleaned by a predetermined method was provided as a base material,and AL 1254 (manufactured by JSR Corporation) was provided as analigning film material. The aligning film material was coated byflexographic printing onto the glass substrate to form a 600angstrom-thick aligning film.

Next, polarized ultraviolet light was applied to the aligning film at 5J/cm² in a direction vertical to the base material to form an aligningfilm by a photoalignment method to which monoaxial anisotropy had beenimparted.

For comparison, a base material provided with an aligning film subjectedto the conventional rubbing treatment was prepared.

2. Preparation of Ink for Phase Difference Control Layer

Ultraviolet-curable acrylate group-containing RMM 34 (manufactured byMerck & Co., Inc.) was used as a liquid crystal material for phasedifference control layer formation. 20 parts by weight of RMM 34 wasdissolved in propylene glycol monomethyl ether acetate as a solvent toprepare a composition for phase difference control layer formation.

3. Formation of Phase Difference Control Layer

Next, the composition for phase difference control layer formationprepared above was spin coated onto the base material with the aligningfilm formed thereon by the photoalignment method. For comparison, thesame composition was coated on the base material with the aligning filmformed thereon by the rubbing method.

Both the substrates with the composition coated thereon were heated on ahot plate at 100° C. for 5 min to remove the residual solvent and thusto develop a liquid crystal structure. Next, ultraviolet light wasapplied (500 mJ/cm², 365 nm) to fix the liquid crystal structure andthus to form a phase difference control layer.

Thus, phase difference control components comprising a phase differencecontrol layer provided on a base material through an aligning film wereprepared.

4. Measurement of Level of Phase Difference in Phase Difference ControlComponent

Next, for the phase difference control components, retardation values(Re; nm) representing the level of phase difference were measured byvarying the observation angle (an elevation angle) in the range of −45degrees to +45 degrees in the slow phase axis direction. RETS-3100 VA,manufactured by Otsuka Electronics Co., Ltd. was used for themeasurement. The results of measurement are shown in FIGS. 4 and 5.

FIG. 4 shows the results of measurement for the phase difference controlcomponent according to the present invention prepared by forming analigning film by photoalignment and providing a phase difference controllayer formed of a liquid crystal material on the aligning film. FIG. 5shows the results of measurement for the comparative phase differencecontrol component prepared by forming an aligning film by theconventional rubbing method and providing a phase difference controllayer formed of a liquid crystal material on the aligning film.

In the case of the photoalignment method shown in FIG. 4, phasedifference properties are symmetrical with respect to the angle ofvisibility. On the other hand, as can be seen from FIG. 5, in the caseof the aligning film formed by the rubbing method, phase differenceproperties are asymmetrical. These results show that, in the phasedifference control component according to the present invention preparedby the photoalignment method, bringing the pretilt angle of liquidcrystal molecules constituting the phase difference layer tosubstantially 0 degree can realize a high level of symmetry of the phasedifference and an effective increase in angle of visibility.

Further, a liquid crystal display device prepared using the phasedifference control component by the photoalignment method according tothe present invention shown in FIG. 4 exhibited display which wasexcellent in symmetry of the angle of visibility.

1. A phase difference control component comprising: a base material; anda phase difference control layer formed of a fixed liquid crystalmaterial provided on said base material through a photo-aligned aligningfilm, wherein the photo-aligned aligning film develops a liquid crystalstructure in which liquid crystal molecules, present at the interface ofthe photo-aligned aligning film and the phase difference control layer,are aligned at a pretilt angle of substantially 0 degree.
 2. The phasedifference control component according to claim 1, wherein said phasedifference control layer has positive birefringence properties and theoptical axis thereof is parallel to the plane of the phase differencecontrol layer.
 3. The phase difference control component according toclaim 1, wherein the liquid crystal material comprises athree-dimensionally crosslinkable compound upon exposure to ultravioletlight selected from the group consisting of formulae (I) to (XI):


4. The phase difference control component according to claim 3, whereinsaid phase difference control layer has positive birefringenceproperties and the optical axis thereof is parallel to the plane of thephase difference control layer and the liquid crystal material comprisesone or more of the three-dimensionally crosslinkable compoundrepresented by formulae (I) to (XI).
 5. The phase difference controlcomponent according to claim 1, wherein the base material comprisestriacetylcelluloses or glass.
 6. The phase difference control componentaccording to claim 1, wherein the base material comprisestriacetylcelluloses or glass, said phase difference control layer haspositive birefringence properties and the optical axis thereof isparallel to the plane of the phase difference control layer.
 7. A phasedifference control component comprising: a base material; and a phasedifference control layer formed of a fixed liquid crystal materialprovided on said base material through a photo-aligned aligning film,wherein the photo-aligned aligning film develops a liquid crystalstructure in which liquid crystal molecules, present at the interface ofthe photo-aligned aligning film and the phase difference control layer,are aligned at a pretilt angle of substantially 0 degree, and whereinthe photo-aligned aligning film is photodimerization type formed of acompound having a cinnamate group.
 8. The phase difference controlcomponent according to claim 7, wherein said phase difference controllayer has positive birefringence properties and the optical axis thereofis parallel to the plane of the phase difference control layer.
 9. Thephase difference control component according to claim 7, wherein theliquid crystal material comprises a three-dimensionally crosslinkablecompound upon exposure to ultraviolet light selected from the groupconsisting of formulae (I) to (XI):


10. The phase difference control component according to claim 9, whereinsaid phase difference control layer has positive birefringenceproperties and the optical axis thereof is parallel to the plane of thephase difference control layer and the liquid crystal material comprisesone or more of the three-dimensionally crosslinkable compoundrepresented by formulae (I) to (XI).
 11. The phase difference controlcomponent according to claim 7, wherein the base material comprisestriacetylcelluloses or glass.
 12. The phase difference control componentaccording to claim 7, wherein the base material comprisestriacetylcelluloses or glass, said phase difference control layer haspositive birefringence properties and the optical axis thereof isparallel to the plane of the phase difference control layer.
 13. A phasedifference control component comprising: a base material; and a phasedifference control layer formed of a fixed liquid crystal materialprovided on said base material through a photo-aligned aligning film,wherein the photo-aligned aligning film develops a liquid crystalstructure in which liquid crystal molecules, present at the interface ofthe photo-aligned aligning film and the phase difference control layer,are aligned at a pretilt angle of substantially 0 degree, and whereinthe retardation value of said phase difference control componentrepresenting the level of phase difference, measured by varying theobservation angle in the range of −45 degrees to +45 degrees in the slowphase axis direction, is symmetrical with respect to the observationangle.
 14. The phase difference control component according to claim 13,wherein said phase difference control layer has positive birefringenceproperties and the optical axis thereof is parallel to the plane of thephase difference control layer.
 15. The phase difference controlcomponent according to claim 13, wherein the liquid crystal materialcomprises a three-dimensionally crosslinkable compound upon exposure toultraviolet light selected from the group consisting of formulae (I) to(XI):


16. The phase difference control component according to claim 13,wherein said phase difference control layer has positive birefringenceproperties and the optical axis thereof is parallel to the plane of thephase difference control layer and the liquid crystal material comprisesone or more of the three-dimensionally crosslinkable compoundrepresented by formulae (I) to (XI).
 17. The phase difference controlcomponent according to claim 13, wherein the base material comprisestriacetylcelluloses or glass.
 18. The phase difference control componentaccording to claim 13, wherein the base material comprisestriacetylcelluloses or glass, said phase difference control layer haspositive birefringence properties and the optical axis thereof isparallel to the plane of the phase difference control layer.